x4+4x2+16 x4+4x2+16 factorizamo
------------------- = +4x2 -4x2
x3 - 8 -------------------------
( x4+8x2+16)-4x2
(x2+4 )^2-4x2
(x2+4+2x)(x2+4-2x)
(x2+2x+4)(x2-2x+4)
(x2+2x+4)(x2_2x+4) x2-2x+4
---------------------------- =-----------
( x+2)(x2+2x+4) x+2
